Can opthalmic beta-blocker increase central apnea events??

[verysincere]

I've become suspicious that twice-daily use of Timolol Maleate (0.5%), a beta-adrenergic blocking agent, may have raised my AHI, perhaps primarily through increased central apnea events. I've dropped the eye-pressure lowering eye drops for two days now and my OSCAR numbers (AHI and frequency and duration of central-apnea events) are somewhat improved. I will reserve judgment until I have at least 10 nights of data but I'm curious if anyone else has had a similar experience. 

A life-time of exercising has giving me a healthy dose of "runner's bradycardia" but it seems like my resting heart rate has dropped even further since I started Timolol in December. There's lot of peer-reviewed medical literature about the association between apnea and bradycardia but most of the studies are about apnea leading to bradycardia, not the drug-induced vice versa. I found a few articles describing beta-blockers as helpful in reducing AHI but we are all familiar with drug side effects lists including warnings of opposite problems:  "This medication may cause drowsiness . .  or insomnia."

[DH575]

I think a would accept a good deal of CA events before giving up Combigan.
Not a good trade off for me. I can buy a machine to stop CA events but no option to buying a new optic nerve.

[OpalRose]

I have my eye pressure checked every 4 months.  It has increased over the last couple years, but holding steady now.  I'm not currently on preventative drops.  

If your eye pressure is too high it can lead to glaucoma and blindness.  Personally, I would gladly use eye drops to preserve my vision than worry about an increase in CA's.

Post a graph of the daily page in OSCAR.  We may be able to help you optimize your therapy with some tweaks to settings.  
You are using a VAuto, which doesn't treat CA's, but the CA's can sometimes be minimized by adjusting the trigger setting to high or very high.

[SarcasticDave94]

I'm in agreement with the others. A bit of CA is worth the eyesight. Use that high trigger setting and CA do tend to go down for most. Just to err on the side of caution, keep tabs on the CA on your OSCAR report.

[verysincere]

If your eye pressure is too high it can lead to glaucoma and blindness.  Personally, I would gladly use eye drops to preserve my vision than worry about an increase in CA's.

I have high pressure in just one eye due to repeated retinal detachment surgeries.  That eye is not particularly useful and if I had to make a choice between preserving that limited eye and eliminating the daytime fatigue caused by my apnea events, I would reluctantly but willingly give up that eye.  Fortunately, there are better options, such as replacing Timolol with another class of IOP-reducing medications.  (Before I do that, I will continue this experiment for a while to establish whether the opthalmic beta-blocker is a significant factor in my increase of apnea events. I try to manipulate variables one at a time but that's not always a simple matter.)

Post a graph of the daily page in OSCAR.  We may be able to help you optimize your therapy with some tweaks to settings.  

Much appreciated!

I have attached my OSCAR page from last night (without Timolol proprionate) and another from about a week ago when I was still using Timolol twice-per-day.  (My rested heart rate has also increased a bit without the Timolol, which I expected.)

I have also included a screen capture for a nearly minute long obstructive apnea---just for kicks---and I can provide more context (and some central apnea examples) if anyone is willing to scrutinize a string of my apnea events.

I find that if I can get at least 6.5 hours of sleep with a AHI<5, my daytime fatigue is bearable---but if the AHI goes over 6 or 7, I feel lousy the next day. (In addition to fatigue, I get abdominal pain.  I assume that someone will say, "The abdominal pain is probably from aerophagia." but even though I have dealt with aerophagia at times, I know from the 1990's and even from when I finally got diagnosed and put on low-pressure CPAP in year 2000, that those are two different sensations.)
 

You are using a VAuto, which doesn't treat CA's, but the CA's can sometimes be minimized by adjusting the trigger setting to high or very high.

Yes, I'm going to suggest that to my doctor but I'm in my initial evaluation period with Medicare for the new VAuto machine. (I had twenty years of CPAP and Turner-Adaptive-Position dental device experience before moving in October to the AirCurve.) So I want to get past all the approval issues before rocking the boat. (I'm not sure how my doctor would react to seeing machine setting changes on his celular telemetry report.) On the other hand, I might sneak a tweak on the trigger setting for a few nights if I'm feeling cocky and tired of the central apneas.

Now that I'm on Medicare, I'm assuming that getting ASV approved will be out of the question without much higher numbers, despite my daytime fatigue and pain issues.

Thank you all for replying to my query, my first on this board.

[SarcasticDave94]

FWIW I'm on Medicare and recently was sent an ASV. So they do approve the machine is medically necessary.

What's the info from the sleep study, specifically the event breakdown numbers and type. AHI was x, Obstructive were x, central x, mixed x, hypopnoea x. Were CA recorded as 50% or more of your Apnea events on that test? If yes, ASV is indicated.

Even so, you might be able to tweak this PAP to keep CA down via a high Trigger and/or minimizing pressure swings and not using any Ramp.

[verysincere]

What's the info from the sleep study, specifically the event breakdown numbers and type. AHI was x, Obstructive were x, central x, mixed x, hypopnoea x. Were CA recorded as 50% or more of your Apnea events on that test? 

The OSCAR screens I posted above (in my previous post) include one night where CA was above 50% (a "typical" bad night) and one night where my numbers were better and the CA was under 50%.

Even so, you might be able to tweak this PAP to keep CA down via a high Trigger and/or minimizing pressure swings and not using any Ramp.

I hadn't used the ramp feature for nearly twenty years but suddenly found myself using a 15minute ramp time in recent months when the pressures on my new bi-level machine were just too strong to handle so abruptly when I start a sleep session.

[OpalRose]

Ultimately, you may need to lower the pressure support just a little. This might bring down the CA's. It's something you'll have to experiment with. If you are not comfortable with making changes without doc's approval, go through him/her first. Obstructives can be tamed by raising the EPAP setting, but I wouldn't recommend changing more than one thing at a time. Then watch for a few days.

As far as changing the Trigger setting, that isn't something he would be aware of. It's not going to show up on any reports. It's probably set to Med as default, move it to High to see if it makes a difference in CA's.

[SarcasticDave94]

Adding in a bit of info: most insurances are only concerned with usage compliance and not setting changes nor who changes them.

[verysincere]

As far as changing the Trigger setting, that isn't something he would be aware of.  It's not going to show up on any reports.  It's probably set to Med as default,  move it to High to see if it makes a difference in CA's.

After setting the Trigger setting to its highest level, I've had two nights of ZERO CA's.   (My CAs and OAs had been much lower lately due to increasing the elevation of the head of my bed---nearly to 20 degrees---but I hadn't had a night of zero CAs in months.)  So my hearty THANKS go to everyone who recommended a higher Trigger setting.

I have posted some screenshots in case there is anything noteworthy within them.  Last night wasn't as low in OAs as the previous night but as long as I have an AHI<5, I'm definitely encouraged. 

I tend to have sleep transition events, especially after my first four or five hours of sleep when I seem to have more difficulty staying asleep.

In the past I rarely showed hypopnea events but now they sometimes appears when my CAs are very low or absent. Is that because the hypopneas are no longer "growing" into full-fledged apnea events? (Or is that unrelated?)

Ultimately, you may need to lower the pressure support just a little.  This might bring down the CA's.  It's something you'll have to experiment with.  If you are not comfortable with making changes without doc's approval, go through him/her first.  Obstructives can be tamed by raising the EPAP setting, but I wouldn't recommend changing more than one thing at a time.  Then watch for a few days. 

When I lower the pressure support, should I go very gradually in 0.2cm/H2O increments and test several nights at the same level, or do you recommend a larger change?

I have medication, diet, and other variables changing of late so I'm going to wait for things to stabilize for a while (and get some blood lab tests) before lowering the pressure support.  OSCAR has been a big help in allowing me to experiment with metabolic tweaks such as carbohydrate intake late in the day and the timing of the evening meal.  (I have found that consuming my modest carbs around 3.5 hours before sleep improves my sleep greatly. I used to follow a 10am-Breakfast & 4:30pmDinner schedule in order to observe a nightly fast of 17.5 hours. It was wonderful for weight and blood glucose management but it turned out to be harming my sleep.)

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My first night at the high Trigger setting had an even better AHI so I've attached the screenshot in case it is helpful.